Green Building Source

Green Building News
April 2005

April 27, 2005

New Soy Adhesive Developed for Wood Products

Researchers from the College of Forestry at Oregon State University have developed a new group of adhesives that may revolutionize a large portion of the wood products industry - and have important environmental and economic benefits.

The discovery has already resulted in three pending patents and should lead to a wide range of new products. But it was originally based on the aroused curiosity of Kaichang Li, an OSU assistant professor, who was harvesting mussels one day from their rocky home at the ocean's edge.

Li observed mussels being pounded by ocean waves, and wondered how they could cling so tenaciously to rocks by their thread-like tentacles.

"I was amazed at the ability of these small mollusks to attach themselves so strongly to rocks," said Li, who is an expert in wood chemistry and adhesives in the OSU Department of Wood Science and Engineering. "Thinking about it, I didn't know of any other type of adhesive that could work this well in water and withstand so much force."

Li decided to look much more closely at the chemistry of the mussels' byssus, which are small threads that attach them to rocks and other surfaces. The byssus thread is a protein with a very unusual composition - an abundant level of a phenolic hydroxyl group and an amino group - that results in the ability of mussels to stick tightly to surfaces despite being inundated in water.

"Clearly the mussels have evolved with the ability to make this protein so they can cling to rocks despite wave forces," Li said. "It's quite remarkable, just an incredibly unique natural feature."

The mussel protein is a superior adhesive, but not readily available. In trying to identify a protein that could be adapted for this purpose, Li had another inspiration at lunch - while eating tofu.

"Soy beans, from which tofu are made, are a crop that's abundantly produced in the U.S. and has a very high content of protein," Li said.

Soy protein is inexpensive and renewable, but it lacks the unique amino acid with phenolic hydroxyl groups that provide adhesive properties. Li's research group was able to add these amino acids to soy protein, and make it work like a mussel-protein adhesive. Then they began to develop other strong and water-resistant wood adhesives from renewable natural materials using mussel protein as a model.

The new wood adhesives are made from natural resources such as soy flour and lignin. They may replace the formaldehyde-based wood adhesives used to make some composite products such as plywood, oriented strand board, particle board, and laminated veneer lumber products - all major components of home construction and many other uses.

One of these patented adhesives is currently cost-competitive with a commonly used urea-formaldehyde resin, researchers say, but does not use formaldehyde or other toxic chemicals. Formaldehyde fumes are associated with some health problems, including eye and throat irritation. The chemical has been shown to be a human carcinogen, and in some circumstances it may be a concern in some residential building products.

The other key advantage of the new adhesives is their superior strength and water resistance.

"The plywood we make with this adhesive can be boiled for several hours and the adhesive holds as strong as ever," Li said. "Regular plywood bonded with urea-formaldehyde resins could never do that."

The first commercial application of the adhesive will be to make decorative hardwood plywood for high-quality interior uses. But the adhesive can also be used in making softwood plywood, particleboard, medium density fiberboard, oriented strand board, and the laminated veneer lumber that is finding increasing use to replace conventional joists and beams in construction.

Techniques have also been explored to create the new adhesives from tree bark or wood decayed by brown rot fungus. Regardless of the material used to produce the adhesives, they are renewable and may reduce the need for the used urea-formaldehyde wood adhesives that have health concerns, and are based on increasingly expensive petroleum.

New ULI Booklet, Higher-Density Development: Myth and Fact

Higher-Density Development: Myth and Fact, dispels eight common myths and provides profiles of 16 projects around the country where higher-density development has proved successful in creating livable communities. "While the benefits of higher-density development are often understated, so are the detrimental effects of low-density development," says author Richard Haughey, ULI’s director of multifamily development.

Developing at a higher density offers the best solution for managing growth and protecting the environment by placing growth in areas already developed with basic infrastructure instead of pushing it further out from the core community, Haughey notes.

The book explores common myths surrounding higher-density development, such as:

Higher-density development overburdens public schools and other public services and requires more infrastructure support systems.

Higher-density development creates more regional traffic congestion and parking problems than low-density development.

Higher-density development leads to higher crime rates.

Higher-density development is environmentally more destructive than lower-density development.

Higher-density development is unattractive and does not fit in a low-density community.

No one in suburban areas wants higher-density development.

Higher-density development is only for lower-income households.

According to the booklet, studies show that when surveyed about higher-density development, people tend to have a negative view. But when shown images of higher-density versus lower-density development, people often change their perceptions and prefer higher density. In a recent study by the National Association of Realtors and Smart Growth America, six in 10 prospective homebuyers said they preferred a neighborhood with a shorter commute and amenities such as shops, restaurants, schools, libraries and public transportation within walking distance over a large-lot neighborhood with a longer commute and limited options for walking.

Higher-Density Development points out that "Increasing density provides a real economic boost to the community and helps pay for the infrastructure and public services that everybody needs." The book notes that some of the more desirable neighborhoods in America are higher density, such as Georgetown in Washington, D.C., Beacon Hill and Back Bay in Boston and Lincoln Park in Chicago.

While the booklet emphasizes the positive aspects of higher-density development, it also acknowledges the challenges of overcoming suburban growth patterns of single-family houses on big lots. But, it concludes, "Well-placed, mixed-use, higher-density development in the suburbs are increasingly popular, creating a new sense of place." In fact, it notes that concerns about the market for higher-density development no longer exist in communities like Celebration in Florida and King Farm in Maryland, which have experienced rapid home price increases due to high buyer demand.

This new booklet was developed by the Urban Land Institute (ULI) in partnership with the Sierra Club, the National Multi Housing Council, and the American Institute of Architects.

House Dust: Toxic Menace?

Toxic chemicals common to home furnishings and electronic equipment have been found in household dust, including chemicals internationally recognized as harmful or toxic to the immune and reproductive systems; babies and young children are particularly at risk from exposure. That is the finding of a recent report, Sick of Dust: Chemicals in Common Products, conducted by Clean Production Action. The study investigated six classes of chemicals in dust samples taken from 70 homes in seven states across the U.S. Among the chemicals documented in household dust are two -- phthalate plasticizers and organotin stabilizers -- that are ubiquitous in PVC vinyl building materials.

Over 90 percent of phthalates manufactured are used in PVC products, and have been documented as leaching from shower curtains and flooring. [2] Animal studies have found phthalates disrupt reproductive systems, particularly in male offspring, and can contribute to male infertility. [3] Phthalates have also been linked to asthma and respiratory problems in children. [4]

Organotins, which are found in PVC water pipes, PVC food packaging materials, and many other consumer products, are poisonous in even small amounts, and can disrupt the hormone, reproductive, and immune systems.

In addition to the two chemicals commonly associated with PVC building materials, the report also found high concentrations of brominated flame retardants, which are incorporated into many plastics, including PVC, and electrical goods. Studies have revealed the breast milk of American women has 10 to 100 times higher concentration of PBDE, a type of flame retardant, than European women.

Washington State Passes First Green Building Law

Washington has become the first state to require all state buildings to meet green construction standards through a legislative act. Governors in several other states have issued executive orders concerning green building.

Gov. Christine Gregoire signed the high performance green buildings bill into law in April.

“With this bill, Washington state is taking the lead to build schools and other state buildings that do a much better job of protecting Washington’s air, land and water,” Gregoire said at a signing ceremony at Washington Middle School in Olympia. A planned remodeling and addition to the school will meet the U.S. Green Building Council standards for such things as using recycled materials, ensuring better ventilation in buildings and reducing water and energy use.

Under the new law, all major public agency facilities exceeding 5,000 square feet, including school buildings receiving state funding, would be required to meet the green building council’s Leadership in Energy and Environmental Design (LEED) standards.

Gregoire noted that the new buildings will not only help protect the environment, but also produce considerable savings in operating costs. The Washington Middle School project, for instance, will help the Olympia School District:

Save more than 500,000 gallons of water each year.

Provide healthier air quality for students by using natural ventilation in classrooms. An added bonus will be saving $1,200 a year in lieu of conventional air conditioning.

Use natural lighting and lighting controls to produce an energy saving of 50 cents per square foot, or $25,000 over a 30-year period. Studies have also shown that properly designed day-lit classrooms have increased student learning and test scores.

According to the State Board of Education and Superintendent of Public Instruction’s office, use of sustainable building designs result in:

“This law shows that smart policies are pro-environment, pro-business and pro-people,” said Joan Crooks, executive director of the Washington Environmental Council. “They improve our lives through better places to live and work while saving money and protecting our environment.”

Clothes Washer to Achieve Greater Efficiency

The U.S. Department of Energy (USDOE) will increase standards for clothes washers carrying the ENERGY STAR® label. The new, tougher ENERGY STAR® criteria which will greatly benefit consumers will also, for the first time, include water savings requirements.

The USDOE projects that this new criteria could result in savings of over $52.8 million annually for American families. The new washers will save over 185.7 million kWh (kilowatt hours) of energy per year, enough to light every household in Washington, D.C., for eight months; and approximately 8.9 billion gallons of water each year, equivalent to the amount of water that flows over Niagara Falls in four hours.

The new criteria will go into effect on January 1, 2007, when tougher minimum efficiency standards for all clothes washers take effect. Under these guidelines, ENERGY STAR®-qualified models will be 36 percent more efficient than the washers meeting the minimum requirements.

In 1997, less than one percent of clothes washers qualified for the ENERGY STAR® label. Today, ENERGY STAR® clothes washers account for over 30 percent of all units sold throughout the United States, and more and more efficient models are becoming available each year.

The new criteria affect the Modified Energy Factor, or MEF, a composite measure of washer efficiency. The higher the MEF, the more efficient the clothes washer. The current MEF will be increased from 1.42 to 1.72. The new criteria also sets the water factor at 8.0. Water factor describes the amount of water used, with a lower water factor indicating less water used per cycle and higher water efficiency.

Award to Recognize Smart Growth Achievement

Recognizing that communities will grow, many have adopted policies and implemented programs to guide growth toward desirable goals. Often called "Smart Growth", these development practices support environmental goals. These include:

The US Environmental Protection Agency will grant five awards to communities that have shown how the principle of smart growth can work in practice. The awards will be given only to state and local governments. Although public-private partnerships may apply, the award will be given to the government entity. Awards will be given in five categories: Build Projects, Policies and Regulations, Small Communities, Military Base Redevelopment and Overall Excellence.

Applications are due May 18, 2005 for activity that has taken place since May 19, 2000. More information, application forms and information on previous years' winners can be seen at the EPA's Smart Growth Web site.

Antron Announces Design Award Competition

The 22nd Antron fiber Design Award competition is now accepting entries. Since 1983, the Antron® Design Award program has recognized designers who are setting new standards of creativity in commercial interior design through the innovative use of carpet. The Antron® Design Award competition celebrates the marriage of unique interior design and inventive floor coverings.

The competition also marks the third year for the Sustainable Flooring Performance Award. The Sustainable Flooring Performance Award recognizes sustainable practices through the use of performance driven flooring choices in commercial applications.

“It is important to recognize architects and interior designers for their innovative work as well as to award sustainable decisions by facility managers around the world,” says Bobby Berrier, vice president –INVISTA commercial and transportation flooring. “Every year, these individuals raise the standards of creativity through their innovative use of carpet.”

Judges for the 22nd Antron® Design Award and the Sustainable Flooring Performance Award will be Gail Burns of WHR Architects, Nila Leiserowitz of Gensler, Brenda Nyce-Taylor of Hillier Architecture, Joseph Pettipas of HOK Canada and George Scammell of the Walt Disney World Company.

Entries are due September 16, 2005. The call for entries and a list of past winners are available at the Antron® Web site.

The Oikos® site is devoted to serving professionals whose work promotes sustainable design and construction. That's a broad goal, but then environmental sustainability touches virtually every aspect of a building. Oikos is a greek word meaning house. Oikos serves as the root for two english words: ecology and economy. That may seem contradictory at first, but it makes perfect sense.